Gordon Brown has announced more than £39bn in government spending since he became prime minister, revealing the extent to which a new era of cooperation between No 10 and the Treasury has allowed him to dominate the news agenda and reap political dividends.

Much of the money would normally have been revealed in the 2007 comprehensive spending review, due in October.

The huge sum suggests that, as chancellor, Mr Brown was able to hold back funds and policy initiatives until Mr Blair had stood aside. In effect, this helped fund the "Brown bounce" that has delivered a run of significant poll leads and added to the expectation of an early general election.

The £39.32bn calculation has been made by the Guardian after analysing every government announcement in the Commons, either oral or written, since Mr Brown came to power seven weeks ago. A total of 40 have been delivered, not all of them with a price tag attached.

The main spending decisions revealed by Mr Brown and Alistair Darling, the chancellor, include:

· An extra £7.7bn for defence to 2011, a 1.5% average real terms increase, excluding the cost of operations met from the reserve.

· £15bn to 2014 to improve the railways, including £5bn for Thameslink, an extra 1,300 carriages to ease overcrowding and more than £500m to tackle bottlenecks in Birmingham and Reading.

· £4bn extra spending on early years education over three years, covering Sure Start centres to 2010-11.

· £8bn on increasing the availability of affordable housing over the next three years, a £3bn increase compared with the previous spending review. This figure is on top of continuing investment in decent homes, including more than £2bn on the arm's length management organisation programme over the next three years.

These spending levels do not imply that the Treasury is going to break the already announced commitment to increase public spending by only 1.9% a year through the three years of the spending review, but they do show the advantages of a coherent relationship between Treasury and No 10.

Ministers announced in the summer that the comprehensive spending review would be published in October, setting out budgets for the three-year period from April 2008. Mr Brown has already announced that spending increases will slow down to 1.9% a year in real terms, half the rate of growth in the previous spending round.

Other specific spending pledges made since Mr Brown took over as prime minister include £800m spending by 2011 on flood defences and the go-ahead for a £1.2bn on a new electronic border system.

In education, £400m of extra spending has been pledged for providing full grants to 50,000 extra students from families with incomes up to £25,000; £184m extra funds to improve youth facilities, including a youth club in every constituency; and £100m on school sports.

The spending pledges have inevitably fuelled talk of Mr Brown planning for an early general election. He sprang a surprise by installing one of his senior cabinet colleagues, Douglas Alexander, as Labour's election coordinator three days before he became prime minister. He has given another, Ed Miliband, the task of writing Labour's election manifesto. His announcements can be seen at least in part as coming from the same motivation: to put Labour on an election footing. Much of the money is going to big regional infrastructure projects or on small-scale, populist measures.

Mr Brown is considering and preparing for a general election next May. There is an outside chance he may go earlier if the Tory implosion continues, although poor economic news may delay him.

So far the polls have done little to discourage Mr Brown from going to the country. A YouGov poll for the Sunday Times at the weekend saw him break through to a double-figure lead over the Conservatives, 42% to 32%. The last ICM poll for the Guardian put Labour six points ahead.